Monday, June 2, 2008

Children of the Sea Corn

Ganking a crochet technique applied to metal coat-hangers used to protect lady’s delicates from wrinkling, this gorgonian coral was crafted with pipe-cleaners and orange yarn during a marathon of circa-1993 Kids in The Hall episodes.

Primona resedaeformis, known locally as sea corn or rice crispy corals, are some of the most common species of coral found off the coast of Nova Scotia, often in association with Paragorgia arborea, crocheted and blogged earlier here.Like other gorgonian corals, sea corn generally grows in a bushy formation, with thin branching stems extending from a short main trunk. The branches are made up of colonies of individual polyps, which extend sticky tentacles called nematocysts into the current to fish for meals of plankton and dissolved organic matter.

As bottom hook and line fishermen have known for generations, these underwater coral forests provide vital habitat for a wide assortment of marine species, including commercially significant fish like pollock and redfish. The nurturing arms of sea corn offer protection from predation and currents, and even boost the feeding ability of other filter-feeders like brittle stars, who perch in the branches.

Much like our crafted version, Primona resedaeformis grow very slowly. They can live for several centuries, growing only a few centimeters a year. Over time, thin deposits of calcium carbonate, (CaCO3) accumulate on the coral branches, from the built up skeletons of successive generations of polyps. These layers can be examined much like growth rings on a tree, and contain valuable information about climate change, along with its alarming ‘sister crisis’, ocean acidification. (Photo courtesy of DFO.)